Generally, carbonized materials such as wood charcoal, bamboo charcoal, coconut shell charcoal, and palm empty fruit bunch charcoal for which various plants including wood, bamboo, coconut shells, and palm empty fruit bunches have been carbonized have porous structures and exhibit excellent adsorption functions, and therefore have been widely used not only for fuels but also in various industrial fields, without being limited to consumers fields, of moisture absorbing materials, deodorizing materials, water quality improving materials, adsorbing materials, etc. Therefore, providing high-quality carbonized materials having constant adsorbing functions has been demanded. Now, as methods for making such carbonized materials, carbonized material production kilns provided as movable types are conventionally known (refer to Patent Documents 1 and 2), but there has been a problem that because of being a movable type, the carbonized material production kiln has a small capacity and cannot therefore produce a large amount of carbonized materials at one time. Therefore, carbonized material production kilns provided as stationary types so as to produce a large amount of carbonized materials at one time are known (refer to Patent Documents 3 and 4).
However, because either type of these performs a step of producing carbonized materials in a closed manner, not only a fire hole and a ceiling cover are required, but a new raw material supply according to a volume reduction is also virtually impossible when raw materials are reduced in volume with carbonized material production, and only raw materials loaded at first can be carbonized, so that there is still a problem in the point of producing a large amount of carbonized materials.
Therefore, the inventor of the present invention has developed an open-type carbonized material production kiln and proposed one that allows newly adding raw materials according to a volume reduction, when raw materials are reduced in volume with carbonized material production (refer to Patent Document 5).